Whole blood made simple

Examples of assays

1. IC50 comparison on multiple donors

Compound A has been found to inhibit LPS-induced TNF release. IC50 will be measured in whole blood assays to assess donor to donor variation.

Assay design: fresh whole blood from 8 different donors is preincubated with increasing concentrations of compound A and treated or not with LPS. After 4h incubation, TNF is measured in the supernatants.

Plate layout and results (for illustration only)

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Click for full size image

Conclusion: compound A inhibits LPS-induced TNF production in all the donors tested. IC50 ranges from 1.5 to 10µM.

2. Detection of contaminants

The purification of compound B comprises several decontamination steps to remove contaminants of bacterial origin. A whole blood assay is used to validate the removal of contaminants after each purification step.

Assay design: whole blood from 2 donors is incubated with serial dilutions of compound B sampled after each purification step. After 4h, IL6 is measured in the supernatants.

Plate layout and results (for illustration only)

Click for full size image

Click for full size image

Conclusion: The final product is free of contaminants.

3. Comparison of different adjuvant formulations

A vaccine company wishes to evaluate different formulations of an adjuvant.

Assay design: fresh whole blood from 3 different donors is incubated 4-6h with serial dilutions of each formulation. The release of pro-inflammatory cytokine(s) (e.g. IL1, IL6, TNF) is then measured.

Plate layout and results (for illustration only)

Click for full size image

Click for full size image

Conclusion:

Formulation #1 doesn’t induce a response in any of the donors.

Formulation #3 is as efficient as the positive control.

Formulation #4 is less efficient than formulation #3.

Interestingly, formulation #2 works in donor A and C but not with donor B reflecting donor to donor variations specific to this formulation.